class_docstr: Grappler Clusters.
class_docstr_tok: ["Grappler","Clusters","."]
code: def tf_cluster(self):
      return self._tf_cluster
  
file_path: tensorflow-upstream/tensorflow/python/grappler/cluster.py
imports: import contextlib
  from tensorflow.core.framework import step_stats_pb2
  from tensorflow.core.grappler.costs import op_performance_data_pb2
  from tensorflow.core.protobuf import device_properties_pb2
  from tensorflow.python.grappler import _pywrap_tf_cluster
label_desc: Use image node_id 4 for calling the Cluster obj's underlying member method code with example usage: obj.tf_cluster() and returns: self